It is supposed that the belt velocity VðtÞ is given by
VðtÞ ¼ 1ðV0 þ a sinðOtÞÞ, (4)
where 0p151; V0; a and O are constants with jV0jbjaj.
Eq. (1) in non-dimensional form becomes:
utt c2
1uxx þ
2
2uxxxx ¼ ux cos t 2ðV1 þ sin tÞuxt
2
ðV1 þ sin tÞ
2
uxx, (5)
where t ¼ Ot; x ¼ x=L; c2
1 ¼ c2=ðL2O2
Þ; V1 ¼ V0=a; ¼ 1a=ðLOÞ; 2
2 ¼ EI=ðrAL4
O2
Þ. For real problems
jj51; 2
251.
In the new variable the boundary and the initial conditions take the following form:
u ¼ 0 for x ¼